[intellec7]

We are using two different feedback techniques.

For the linear "joint" (which is not used in the video) there are three stationary reed switches which detect when a magnet (located on the moving telescope section) are within a few millimeters proximity. Using a state machine, controlled motor direction, we infer 5 states of the telescoping arm position bottom, middle, top, and two states for any area between those two intervals. We can then find out where we currently are, and using another state machine, control the motor accordingly to become where we want to be.

The two rotational joints both have banebot encoders. We can infer relative angular position from starting positions (these will eventually be zeroed with limit switched). We implement a simple proportional feedback control. This is especially needed for the last joint (the wrist is what I think we agreed on calling it) because it moves extremely fast.

We saw no need to implement a full PID routine for these joints. We also felt no need to implement any form of mathematical control for the elevator due to the fact that it pretty much stops within very few milliseconds of commanding it to stop.